public void Draw() {
    mCamera.Set();

    /*mShadowMaskObject.Begin();
    {
    	glPushAttrib(GL_COLOR_BUFFER_BIT);
    	{
    		mShadowMaskObject.Clear();

    		glPushMatrix();
    		{
    			glLoadIdentity();

    			glColor3f(0, 0, 0);
    			glBegin(GL_QUADS);
    			{
    				glVertex2f(0, 0);
    				glVertex2f(mGameWindow.Width(), 0);
    				glVertex2f(mGameWindow.Width(), mGameWindow.Height());
    				glVertex2f(0, mGameWindow.Height());
    			}
    			glEnd();
    		}
    		glPopMatrix();
    	}
    	glPopAttrib();
    }
    mShadowMaskObject.End();*/

    CalculateLighting();

    DrawScene();

    // draw mask over scene to occlude shadows
    glPushMatrix();
    {
      glLoadIdentity();

      glColor4f(1, 1, 1, 1);
      Texture.Begin();
      {
        mShadowMask.BindTexture();
        mShadowMask.Draw(0, 0, 1, -1);
      }
      Texture.End();
    }
    glPopMatrix();
  }
  public void Load() {
    mCamera = new Camera(GetGameWindow());

    Light.Load(mGameWindow.Width(), mGameWindow.Height());
    ComplexPolygon.Load(mGameWindow.Width(), mGameWindow.Height());

    mShadowMask = new Texture(mGameWindow.Width(), mGameWindow.Height());

    try {
      mShadowMaskObject = new FrameBufferObject(mShadowMask);
    } catch (Exception e) {
      e.printStackTrace();
    }

    mCamera.ForceScaleFocus((mGameWindow.Width() / 1600.0f + mGameWindow.Height() / 900.0f) / 2);

    mAmbientLighting = 0.0f;
  }
  public void CalculateLighting() {
    mShadowMaskObject.Begin();
    {
      glPushAttrib(GL_COLOR_BUFFER_BIT);
      {
        mShadowMaskObject.Clear();

        // additive blending
        glBlendFunc(GL_ONE, GL_ONE);

        // Draw lights:

        // ambient lighting
        glPushMatrix();
        {
          glLoadIdentity();

          glColor4f(1, 1, 1, mAmbientLighting);
          glBegin(GL_QUADS);
          {
            glVertex2f(0, 0);
            glVertex2f(mGameWindow.Width(), 0);
            glVertex2f(mGameWindow.Width(), mGameWindow.Height());
            glVertex2f(0, mGameWindow.Height());
          }
          glEnd();
        }
        glPopMatrix();

        Vector2 middleScreen =
            mCamera.ScreenToWorld(
                new Vector2(mGameWindow.Width(), mGameWindow.Height()).DividedBy(2));

        Vector2 topLeft = mCamera.ScreenToWorld(new Vector2(0, 0));
        Vector2 topRight = mCamera.ScreenToWorld(new Vector2(mGameWindow.Width(), 0));
        Vector2 bottomRight =
            mCamera.ScreenToWorld(new Vector2(mGameWindow.Width(), mGameWindow.Height()));
        Vector2 bottomLeft = mCamera.ScreenToWorld(new Vector2(0, mGameWindow.Height()));

        SimplePolygon screen = new SimplePolygon(this, middleScreen);
        screen.AddVertexAbsolute(topLeft);
        screen.AddVertexAbsolute(topRight);
        screen.AddVertexAbsolute(bottomRight);
        screen.AddVertexAbsolute(bottomLeft);

        mLevel.DrawLights(screen);

        // blend lights with shadow:
        glPushMatrix();
        {
          glLoadIdentity();

          glBlendFuncSeparate(GL_ONE, GL_ZERO, GL_ONE_MINUS_DST_ALPHA, GL_ZERO);

          glColor3f(0, 0, 0);
          glBegin(GL_QUADS);
          {
            glVertex2f(0, 0);
            glVertex2f(mGameWindow.Width(), 0);
            glVertex2f(mGameWindow.Width(), mGameWindow.Height());
            glVertex2f(0, mGameWindow.Height());
          }
          glEnd();
        }
        glPopMatrix();
      }
      glPopAttrib();
    }
    mShadowMaskObject.End();
  }
 public void Update(GameTime gameTime) {
   mCamera.Update(gameTime);
 }